Sheet Feeder Stopper Mechanism for Jam Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sheet feeders often cause document sheet breakage when a jam occurs due to the stopper being caught by the sheet during forced removal, as users unfamiliar with the jam procedure attempt to pull out the trailing end, leading to improper handling and potential tearing.
Innovation Solution
The sheet feeder incorporates a stopper mechanism that changes postures from a restricting to a feed allowing and then a rotational posture, allowing the stopper to move out of the way when a jam occurs, reducing the pressure exerted on the sheet during removal and preventing breakage by pivoting about designated pivot points.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional stopper mechanism is used that is coupled to the pickup roller via a one-way clutch, then the stopper can restrict the position of the leading end of the document sheet during normal feeding operation, but the stopper may be caught by the document sheet during forced removal when a jam occurs, causing document sheet breakage
Solution Approach 1:
The stopper mechanism is designed to dynamically change its posture between a restricting posture (during normal feeding) and a rotational posture (during jam removal). The stopper pivots about a first rotational pivot point when the holder pivots, allowing it to rotate away from the document sheet path during forced removal, preventing the sheet from being caught and broken while maintaining its position-restricting function during normal operation
Solution Approach 2:
The stopper mechanism is prepared in advance to accommodate both normal feeding and jam removal scenarios. By coupling the stopper to the holder through a supporting body that allows rotation about a first rotational pivot point, the system pre-configures the stopper to automatically assume the appropriate posture (restricting or rotational) based on the operational state, eliminating the need for manual intervention or complex control mechanisms
2Manufacturing precision
If the stopper is positioned to restrict the leading end of the document sheet during feeding operation, then the document sheet is fed properly without oblique posture, but the stopper interferes with the forced removal of jammed document sheets
Solution Approach 1:
The stopper transitions from a static position-restricting component to a dynamic component that changes posture based on operational needs. During normal feeding, it maintains the restricting posture to ensure precise sheet positioning. During jam removal, when the holder pivots to the retracted posture, the stopper automatically rotates about the first rotational pivot point to face in the second direction, clearing the sheet path and enabling easy manual removal without interference
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A sheet feeder 3 includes a stopper member 532 which is a member located in a sheet feeding route and supported on a supporting body 531 rotatably about a first rotational pivot point and the posture of which is changed among a restricting posture in which a contact end portion 538 comes into contact with a leading end SU of a sheet S in a feeding direction to restrict the position of the leading end SU in the feeding direction before a feeding operation of feeding the sheet S by a feeding mechanism 32, a feed allowing posture which is assumed during the feeding operation and in which the contact end portion 538 is separated from the leading end SU in the feeding direction in a first direction F in which the sheet S is fed, and a rotational posture reached from the feed allowing posture by the rotation of the stopper member 532 about the first rotational pivot point so that the contact end portion 538 faces in a second direction opposite to the first direction. The second direction is a direction in which the sheet S is pulled out from the feeding mechanism 32 when a jam occurs in the feeding mechanism 32.